Halve, seed and peel avocado.
Rub lightly with olive oil, salt and pepper, and then place on a high-heat grill for 30 seconds on each side. Set aside to cool.
(The grilling will halt the avocado from browning, so it can be done in advance.)
Halve and arrange tomatoes on a serving plate.
Combine remainder of ingredients in a bowl and toss with dressing to evenly coat.
Place on serving plate; slice and arrange grilled avocado on top.
Serve and enjoy.